Sudden unexpected death in childhood due to eosinophilic myocarditis

A 12-year-old boy with no previous serious medical history experienced abdominal discomfort and chest pains for 5 days and suddenly died. The autopsy revealed diffuse and extensive infiltration of eosinophils into the myocardium, with poorly formed granulomas and few fibrotic changes. The necrotic changes was so extensive that Charcot-Leyden crystals formed. The other visceral organs had no specific pathologic changes except for mild lymphocytic infiltration with an increase in goblet cells in the bronchial areas and eosinocytosis in the blood vessels. An initial viral infection seemed to have caused subsequent eosinophil activation due to an allergic condition. Eosinophilic myocarditis is a rare cause of sudden death in apparently healthy children. Cardiac toxicity of eosinophils is, however, well established and dominates the ultimate prognosis of patients with complicated eosinophilia.